Urticaria Flashcards
Urticaria. also known as
“hives”
Symptom, duration
transient, red, pruritic well-demarcated wheals
• each individual lesion lasts less than 24 h
Epidemiology (prevalence)
second most common type of drug reaction
Physiopathology
- results from release of histamine from mast cells in dermis
- can also result after physical contact with allergen
Summarize, most common etiologies of Acute Urticaria
Drugs: especially ASA, NSAIDs Foods: nuts, shellfish, eggs, fruit Idiopathic Infection Insect stings (bees, wasps, hornets) Percutaneous absorption: cosmetics, work exposures Stress Systemic diseases: SLE, endocrinopathy, neoplasm
Acute Urticaria. How common it is?
> 2/3 of cases
Acute Urticaria. How long does it last?
Attacks last <6 wk
Individual lesions last <24 h
Chronic Urticaria How common it is?
<1/3 of cases
Chronic Urticaria
How long does it last?
Attacks last >6 wk
Individual lesion lasts <24 h
Chronic Urticaria
Summarize, most common etiologies of
IgE-dependent: trigger associated
Idiopathic (90% of chronic urticaria patients)
Aeroallergens
Drugs (antibiotics, hormones, local anesthetics)
Foods and additives
Insect stings
Parasitic infections
Physical contact (animal saliva, plant resins, latex, metals, lotions, soap).
Other. Complement-mediated : Infections, viral/bacterial (>80% of urticaria in pediatric patients)
Urticarial Vasculitis
How long does it last?
Individual lesions last >24 h
Urticarial Vasculitis.
Clinical feature
Often painful, less likely
pruritic, heals with bruise
type lesions
Urticarial Vasculitis. Research
Requires biopsy
Urticarial Vasculitis
etiologies
Idiopathic Infections Hepatitis Autoimmune diseases SLE Drug hypersensitivity Cimetidine and diltiazem
